Three-dimensional full loop simulation of solids circulation in an interconnected fluidized bed

Abstract

ReuseUnless indicated otherwise, fulltext items are protected by copyright with all rights reserved. The copyright exception in section 29 of the Copyright, Designs and Patents Act 1988 allows the making of a single copy solely for the purpose of non-commercial research or private study within the limits of fair dealing. The publisher or other rights-holder may allow further reproduction and re-use of this version -refer to the White Rose Research Online record for this item. Where records identify the publisher as the copyright holder, users can verify any specific terms of use on the publisher's website. TakedownIf you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing eprints@whiterose.ac.uk including the URL of the record and the reason for the withdrawal request. Abstract 3-D full loop CFD simulation of solids circulation rate is conducted in a complicated circulating-fluidized bed, which consists of a riser, a bubbling bed, a cyclone and a loop-seal. The effects of operating gas velocity, particle diameter and total solids inventory on the solids circulation rate are investigated based on the system pressure balance of an interconnected fluidized bed. CFD results indicate that the gas velocity in the riser plays a dominant role in controlling the solids circulation rate, whilst the gas velocity in the pot-seal influences in a narrow operating range. The solids circulation rate is strongly influenced by particle diameter and total solids inventory, but becomes insensitive to the operating conditions in the bubbling bed as the gas velocity is higher than the minimum fluidization velocity.

Comparison of Riser-Simplified, Riser-Only, and Full-Loop Simulations for a Circulating Fluidized Bed

“…With the development of the model and computing capacity, more and more investigators conducted full-loop simulation of the CFB system [14][15][16][17][18][19][20][21][22], which treats the CFB as a whole dynamic system. Chu et al [14] conducted a 3D full-loop simulation for CFB by means of the combined continuum and discrete method.…”

“…The flow regime, especially choking and continuous transitions, was captured by simulation. Guan et al [16] conducted a full-loop simulation of a CFB including the riser, bubbling bed, pot-seal, and cyclone. From the results, they found a strong relationship between the solids flow pattern in the bubbling bed in the return system and superficial gas velocity in the riser.…”

Unsteady three-dimensional theoretical model and numerical simulation of a 120-kW chemical looping combustion pilot plant

“…On the other hand, a small number of studies based on a three dimensional model of a DCFB CLC unit may be found in the lit erature. Guan et al (2014Guan et al ( , 2016 conducted three dimensional (3D) numerical simulations of a cold flow model, scaled from a 30 MW model by Johansson et al (2003), and studied the effects of drag cor relation on the predictions and operating conditions on the solid cir culation rate. Geng et al (2015) used the 3D CFD for reproducing a 120 kW cold flow model of Pröll et al (2009b) and studied the effects of fluidization rate on the solid circulation.…”

Influência do coeficiente de especularidade na simulação computacional do escoamento gás-sólido no ciclone de um leito fluidizado circulante

“…A primeira, apesar de fisicamente mais próxima à realidade e, aparentemente, mais difundida em estudos que consideram somente o ciclone, como ressaltado por Dias (2009), gera um custo computacional maior (VAN WACHEM et al, 2001;CHIESA et al, 2005). Dessa forma, para sistemas com um número elevado de partículas e de volumes de controle na malha computacional, como os circuitos integrados de LFC, ainda se prefere a abordagem Euleriana, como demonstrado nos trabalhos apresentados por Wang et al (2014), Guan et al (2016), Yu et al (2018) e Liu, Zhang e Wang (2019).…”

“…Estes modelos foram utilizados nos trabalhos de Lu et al (2013), Wang et al (2014) e Liu, Zhang e Wang (2019). Todavia, os modelos que consideram o escoamento homogêneo, como o de Gidaspow, de 1994, ainda são amplamente aplicados, como verificado nos trabalhos apresentados por Seo et al (2011), Guan et al (2016), Wang et al (2017) e Wang et al (2018).…”